It may be that only instant major failures are left with this modern equipment? Many recent crashes went without any crew signal.

Even the current work on automatic emergency "pod eject" satcom/VHF technical log signaling is frustrated by the minimal time between trouble onset and impact. You cannot analyze the data fast enough to get more than a minimal report off ship.

I stumbled upon this one which is very near my professional work area and I hope that it does not turn out to be the reason we lost this one.

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777 airplanes. This AD was prompted by a report of cracking in the fuselage skin underneath the satellite communication (SATCOM) antenna adapter. This AD requires repetitive inspections of the visible fuselage skin and doubler if installed, for cracking, corrosion, and any indication of contact of a certain fastener to a bonding jumper, and repair if necessary. We are issuing this AD to detect and correct cracking and corrosion in the fuselage skin, which could lead to rapid decompression and loss of structural integrity of the airplane.

This AD was prompted by a report of cracking in the fuselage skin underneath the satellite communication (SATCOM) antenna adapter.

I was thinking along similar lines. One of Qantas' aircraft, purchased from MAS, was found to have cracks in the fuselage (big enough to see daylight through). It was found that the people working on MAS' aircraft were using sharp metal tools to remove sealant from fuselage joints. This was scoring the metal underneath and weakening the skin. Qantas engineering was carrying out a major check shortly after they purchased the aircraft and discovered the cracks (which could have resulted in a hull loss).

Now only soft plastic tools are permitted. Even micarta tools are not to be used. However, I'm sure MAS would now be using the right tools. That is, of course, if MAS are not outsourcing their maintenance to others.

This event really puzzles me. If the plane broke apart suddenly while enroute, then the debris would probably have been visible right where the searchers were originally looking for it.

And on the other hand, if there was a bad-but-not-fatal condition, then ACARS, the transponder, and radio would have been available for a while, giving some clue as to what was going on (with the first of those two being automatic). Think back to the Air France crash in 2009: the pilots didn't make a distress call, but ACARS started sending automatic maintenance data as systems integrity began to degrade. They had 4 minutes of ACARS data that was sent as the plane was crashing.

However in this case we seem to have an aircraft that was healthy enough to turn left and continue in controlled flight for at least 100 miles off course, while at the same time not sending any automatic maintenance messages, no working transponder, and no communications from the pilots.

I can think of very few scenarios that meet these conditions. One would be a deliberate -- and deliberately stealthy -- diversion by the pilots for some as yet unknown reason.

EDIT: NPR just said that the ACARS data hasn't thoroughly been explored yet... so perhaps there is more data yet to examine.

Radar algorithm shows MH370 with lots of other airplanes. One near MH370 suddenly moves off at three times the speed of all other planes then just stops cold. MH370 then does a right turn, a left turn another right turn then disappears then the other target does the same...! What the?! Anybody else seen this?....and terrorists are NOT that smart! I've disgaurded any kind of link to terrorism based on that radar algorithm

I wonder that ATC does not have reliable radio data and records of that area. Was MH370 on its way heading to Vietnam or did it turn left to the Street of Malakka? In that case, why did no vessel crew recognize an exploding 772 or found debris? Remember, the Malakka street is one of the most frequently used waterways in the world. If the plane didn't crash, where could these guys land a 772 undetected?

Is there no sufficient radar coverage in the region? Neither civil nor military? Or by satellite? Is it possible to turn your ship and fly in the opposite direction while no one cares about it, no one recognizes it, even if you fly some hundred miles in the opposite direction?

Regarding ACARS: We know about the status messages sent by AF447. If a 772 falls into serious technical trouble, will it also generate ACARS messages without pilots permission?

Can't comment on the 777 acars, but here are a few things that I wonder about.

1 Seems like a big coincidence that there was a big oil slick where the airplane was (supposedly) last seen before the transponder signals were lost. There exists a shipping tracking ability in some parts of the world which MIGHT be able to show what ships were in the area and could have produced the slick. Worth looking into!

2 I've seen nothing on the news regarding that AD. Seems like that should be generating some interest if it in fact exists. A loss of pressure in the cabin due to a failure caused by having that antenna depart could start to explain a lot. Particularly if the crew did not get on O2 QUICKLY. or

3 If someone wanted to take the airplane (for whatever reason) shutting down the electronics, raising the cabin altitude to kill all of the passengers, and then descending to a low altitude to get under the radar could work.

Here's a shot of the SATCOM (Inmarsat) tray in the crown, just below the antenna and 10 meters aft of L3:If that area goes, wave goodbye.

NOTE: I have no information whatsoever that this structural failure actually ever happened. Read the AD.

Can somebody shed light on the interwovenness of civilian and military radars and ATC in that area? I believe that civilian radar is pretty scarce there, given the expense. I would not be surprised to learn that ATC is also done by the military.

Military radar is usually much more capable than civilian radar, expecially since military uses primary returns (uncooperative targets) while civilian largely relies on secondary returns (cooperative targets with a transponder). But by opening up the military radar and ATC recordings, Malaysia essentially discloses their military capability. This won't happen easily.

It is quite possible that this incident has already spawned discussion about whether it should be allowed to use classified military equipment and staff to perform civilian safety tasks as a by-product. Not because it does not work, but because it cannot be audited/reviewed/disclosed -- the base of aviation safety.

There are now theories about exploding crew oxygen bottles (similar to the Qantas QF30 incident). The oxygen bottles are contained in the equipment centre and might have affected comms, ATC and pressurisation. With no oxygen and lots of smoke, maybe the pilots became incapacitated? The aircraft could have continued by itself in any direction.

Did the plane really turn around or did it simply generate spurious position data signals?

During a decompression, don't the pilots deselect TCAS RA as they are descending? I'm just wondering if they turned the switch too far and went to OFF or STBY.

More noises about "the engines having sent messages for four more hours after radar contact lost". But:

avherald wrote

On Mar 13th 2014 afternoon Malaysia's Transport Minister said in a televised press conference, that the last ACARS transmission was received from the aircraft at 01:07L (17:07Z), there were no later transmissions via ACARS (editorial note: which effectively states a report by a single US "news" paper of the engines monitoring recording information via ACARS for 4 more hours is untrue)

Wikipedia says that they do, quoting Aviation Week and Space Technology as their source.

Quote

The airline reported in its eleventh press release that all of its aircraft are fitted with an Aircraft Communications Addressing and Reporting System (ACARS), a system that automatically transmits data about the status of the aircraft, but added "Nevertheless, there were no distress calls and no information was relayed."[20]

Much, not all, of the tracking and telemetry technology is there purely for commercial reasons only. The vast majority of ACARS is not for safety, but for dispatch management, some maintenance, and weather.

FANS-1/A and the upcoming LINK2000+ systems use ACARS for safety, mostly a combination of automatic 5-minute position reports over the oceans (i.e., outside any radar cover area) and limited textual air traffic control (CPDLC). These systems are widely used over the Atlantic and Pacific, and will be used over mainland Europe soon, but typically they are less well-represented in the Oriental area.

In all cases, there is little redundancy in these systems. One VHF radio, useless beyond 200 nm of a ground station. One SATCOM, mostly Inmarsat and more and more Iridium, which are not reliable if you disturb the plane. And one HF, even less reliable under good conditions. The system uses exactly one of these at a time to relay stuff and switching radio can take up to ten minutes.

In all cases, emergency stuff is done by voice, period.

The idea that it is simple to track all aircraft out there is quite misinformed. The aircraft know where they are, yes, but there is no global simple reliable cheap lightweight broadband communication system. It is all commercial, very few parts of the system are government/military (GPS comes to mind). Somebody needs to pay for this, and it is the passenger, not the tax payer.

At the higher latitudes, the geostationary Inmarsat satellites become a very hard target to track. Iridium is easier but there you are faced with gaps in between satellites. Theoretically there will never be any spot on Earth without at least one Iridium satellite at 8.5 degrees or higher above the horizon, but coverage holes (dark zones) do occur, handover goofs do occur, and a thunderstorm on the horizon exactly where the satellite is will have you go blank.

Incidentally, CNN is now reporting that the plane was flying on regular airways as it headed out over the Indian Ocean in the direction of the Andaman Islands. Apparently, what ever happened wasn't random or wantonly destructive. Someone had a plan.

During the press conference in the afternoon of Mar 14th 2014 Malaysia's Transport Minister provided more details about the primary radar observation stating, the target was first picked up at waypoint IGARI at FL350 (editorial note: waypoint IGARI nearly conincides with the last secondary radar position of MH-370) at 01:21L moving towards waypoint VAMPI, then waypoint GIVAL and finally turning northwest towards waypoint IGREX. The target was lost at FL295 after GIVAL at 02:15L.

Of course, one primary target looks much like another. They could have been tracking a military plane. Have they calculated the speed of the target? Anything under M0.75 or over M.090 probably wasn't a 777.